College Physics with MasteringPhysics 7th Edition by Jerry Wilson,Anthony Buffa,Bo Lou

Exercise 78

A bat moving at 15.0 m/s emits a high-frequency sound as it approaches a wall that is 25.0 m away. Assuming that the bat continues straight toward the wall, how far away is it when it receives the echo (Assume the air temperature in the cave to be 0 °C.)